In many electronic cabinet housings, mounting boxes containing electronic modules are mounted on one or more sliding racks or rails so that they can be extended away from the cabinet for servicing or access. It is desirable to be able to tilt the box through the vertical plane once it has been extended away from the cabinet, to provide better access to the box for servicing or replacement of parts.
Typically, a positioning and locking mechanism included in the front portion of the slide rack will permit this tilting and locking of boxes. This positioning and locking mechanism is constructed by adding an artificial wall to the end of the slide rack and welding or otherwise securing to this wall a pawl and ratchet. The front portion of the slide rack containing the pawl and ratchet mechanism is then bolted or screwed to the box so that the box and the front portion of the slide rack are able to pivot with respect to slide rack and can also be locked into place.
This apparatus for pivoting and locking the box in place is very complicated to manufacture as part of the slide rack mechanism, especially when the boxes in the cabinet have significant weight, and when space between the boxes or the slide mechanism and the cabinet is small and at a premium. Because the primary purpose of the slide rack is to provide the horizontal sliding motion of the box, it is difficult to optimally locate the pivot point on the slide rack in the place most capable of bearing heavy weight loads. Because the space between boxes in the cabinet is at a premium, the thickness of the slide mechanism is constrained. Thus, the front portion must be made of relatively thin materials and parts, which limits the slide's weight capacity. With these space constraints, complex and expensive mechanisms are required to permit the parts to accomplish their tilting and locking functions without occupying too much space and without breaking or bending under heavier loads.
In the prior art, box removal required the use of detachable slide sections. The detachable section was costly and complicated to manufacture, for it required the addition of failsafe detent stop mechanisms. For example, without the failsafe stop, a box could be pulled from a cabinet at such a velocity as to cause a detent to fail. A detent failure would cause the box to become unsupported with the possibility of injury to the operator.
Consequently it is an object of this invention to provide an integral pivot and locking mechanism for slide rack mounted boxes, such mechanism also being capable of bearing heavier loads. It is another object of this invention to provide a tilting and locking mechanism for a mounting box which is simple to manufacture without any loss of load bearing capacity. Still another object of this invention is to provide a pivoting and locking mechanism for a mounting box which is significantly less expensive to produce and which can be used in conjunction with standard slide racks such as, for example, ball bearing or solid bearing telescoping rail slide systems. Yet another object of this invention is to provide safety features for the tilting and locking mechanism so that accidental pivoting of the mounting box past a pre-determined arc of motion cannot occur. Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings.